motosickle questions

[JeepPhisherman]

Alrighty, I rode my bike to class this morning, and came home. Everything was running fine. Parked it in the garage, ate some lunch. Tried to leave the house about 2 hours later, and the bike is running funny.

It started up fine with choke, but when I switched the choke off, it wasn't running well, a stumbling idle. So, I switched the choke back on, shut the garage and attempted to leave. When I try to take off from a start, the bike is stumbling like it's going to stall out. So, I pull over, turn off choke, restart, same symptoms. Pull the bike back in the garage to fiddle. Turn it on to let it run some thinking it will just go away. Feck around and the bike dies a couple of times on non-choke.

Restart the bike, go to take it around the block and it's still wanting to stall. I have to rev up to 3ish grand to keep it from stalling comming out of first and now the bike has absolutely 0 balls - my saturn ion rental in Cali accelerated better. So, pull back in the garage to check everything out. Air cleaner's dirty, but not dirty enough to cause this ****, but I order a replacement. Pull the plugs, thinking it's probably due to one of the cylinders not firing. Plugs are a little dirty, so I wire brush them, and I'm going to pick up some spares tomorrow.

Now I'm thinking it might be one of the pilots in the carbs, which could be plugged not allowing fuel well enough into the cylinder. (2 carbs on the bike, 1 for each cylinder) Any idea on how to remedy this without removing the carbs? Cause I don't know **** about carbs and don't want to learn now. If I do have to take them off, I'm going to go ahead and rejet and buy or build some new pipes.

Or, is my carb idea stupid. Maybe it's just not firing? But then there should be backfiring, correct?

[Doug Krebs]

Next time feel the pipes to see if they are both hot or if one is much cooler. That will tell you if they are both firing.

What kind of condition is the inside of the tank in? Rusty at all?

Sure it's actually not running out of gas? Like you switched it to reserve but forgot or some crap?

Have you tried spraying carb cleaner into the carbs? I'm assuming on that bike it's not a ***** to get them off.

[JeepPhisherman]

Next time feel the pipes to see if they are both hot or if one is much cooler. That will tell you if they are both firing.

What kind of condition is the inside of the tank in? Rusty at all?

Sure it's actually not running out of gas? Like you switched it to reserve but forgot or some crap?

Have you tried spraying carb cleaner into the carbs? I'm assuming on that bike it's not a ***** to get them off.


The tank is good. The bike has been ridden almost constantly (atleast every month) since it's inception as far as I know. I've had this since Septemberish? and this is the first problem I've had.

I fooled with switching it from reserve and prime and regular, nothing. And this isn't like a running out of fuel problem, I know what those are like...

Getting the carbs off this bike is somewhat of a *****, and I don't have carb cleaner. I think I'm going to pull them and check them out, maybe get a rebuild kit, and I think I might drill out the pilots while I'm at it.

Anyone that knows anything about carbs in CS want to come help tonight/this weekend?

Oh and yes, I missed a class yesterday to work on the bike, but I had to take the truck for the next class, I can't miss that one or no graduate.

[Doug Krebs]

The tank is good. The bike has been ridden almost constantly (atleast every month) since it's inception as far as I know. I've had this since Septemberish? and this is the first problem I've had.

I fooled with switching it from reserve and prime and regular, nothing. And this isn't like a running out of fuel problem, I know what those are like...

Getting the carbs off this bike is somewhat of a *****, and I don't have carb cleaner. I think I'm going to pull them and check them out, maybe get a rebuild kit, and I think I might drill out the pilots while I'm at it.

Anyone that knows anything about carbs in CS want to come help tonight/this weekend?

Oh and yes, I missed a class yesterday to work on the bike, but I had to take the truck for the next class, I can't miss that one or no graduate.

Bike carbs are seriously fickle. I guess it's easier with only 2 carbs, but you'll still have to sync them.

I wouldn't mess with the carbs unless you are certain it's them. I just don't see the carbs as the solution in this case as it was running fine a couple hours earlier.

I would suspect something obvious, or a problem with spark.

Figure out which cylinder it is using the hot/cold exhaust method.

[fbronco86]

I would check for spark on both cylinders. Before diving into the carbs.

I would also leave the carbs and pipes stock. They can make it hard to start. My KLR650 is a hoe to start sometimes.

What kinda bike do you have anyway? I dont remember

[JeepPhisherman]

82 yamaha virago 920 (xv920j)

[KrazyKarl02]

Like mentioned before go start the bike, check the exhaust pipe temperature, make sure both are hot. If one is not hot replace the plugs. If replacing the plugs does not help then I would say you have a fuel issue. Check the obvious (fuel filter, pet****, etc...) If nothing else I would point to the carbs.

Do you have an inline fuel filter? If not a piece of trash or whatever could have been hidden in somewhere and all of the sudden found its way, like you said into the jets, in that case remove carbs and clean. If I lived in College Station I would help. It is not really hard just time consuming and sometimes requires little asian hands.

Like Mike said if you are happy with the speed of the bike I would not re-jet....

[JeepPhisherman]

Replaced the plugs and wires and everything is running as good as it always has now. I guess the front cyliner wasn't firing. Don't know why it wasn't causing back firing though? Wouldn't there still be fuel being dumped into the cylinder and then into the exhaust?

And yea, the only reason I was going to rejet is to get rid of the nasty ugly pipes, but I'm selling the bike in a few months, so I guess I'll just deal with it. Gots work to do on the truck to keep me busy anywho.

[fbronco86]

82 yamaha virago 920 (xv920j)

I heard krebs is an excellent yamaha mechanic.